Disposable email checker
Check an email address or domain against a curated disposable-domain set, naming signals and live public MX records.
A disposable-email verdict is a risk signal, not a fact about the person.
Temporary-mail providers rotate domains, custom domains can be used temporarily and legitimate domains can have unusual names. A responsible checker combines several signals, explains them and preserves an “unknown” result. It should not claim that an address is fraudulent, that a mailbox exists or that a person is untrustworthy.
Curated domain match
The checker compares the domain with a built-in set of well-known disposable and temporary-mail domains. Exact matches are strong evidence, but the set cannot contain every rotating provider domain.
Live public MX
It queries public DNS-over-HTTPS for mail exchangers. An MX answer means the domain publishes a receiving route; it does not prove a particular mailbox exists or will remain available.
Naming and provider signals
Temporary-mail words in the domain or MX hostname raise risk. Established conventional mailbox domains reduce risk. All signals remain visible in the result.
How to use the result in a SaaS signup flow
Do not block every uncertain address. That creates false positives, frustrates real buyers and encourages them to use a different address you learn nothing about. Use progressive controls: allow low-risk addresses, request ordinary verification for unknown addresses, and apply step-up verification or manual review when a known disposable domain appears in a high-consequence workflow.
The consequence matters. A free newsletter can accept more uncertainty than a trial that consumes expensive infrastructure, financial credit or limited inventory. Conversely, requiring a corporate domain for a consumer product destroys conversion without improving safety. Tie the response to measurable abuse cost rather than a blanket dislike of free email.
What this tool deliberately does not do
It does not send a verification message
It does not perform an SMTP mailbox probe
It does not identify the owner of an address
It does not prove fraud, abuse or intent
It does not guarantee the domain will remain active
It does not replace account verification or risk analysis
SMTP mailbox probing is unreliable and can be abusive: many servers accept all recipients, defer decisions, tarpitting probes or hide user existence. The safest proof is a consent-based verification message combined with product-specific abuse controls.
Need a durable business address?
Use a domain you control, create an explicit MailerZ route, protect domain renewal and test account recovery before depending on it.